Show a live picture on a camera tile, run an action from the alert button, roll long media titles, and keep full-page tiles in their own colour (0.2.91)

Live picture (issue #4): a camera or image tile on a Guition takes
Display -> Live picture with a pace of 15 or 30 s. The camera tiles of a
page share one download: the screen asks ESP Screens for them together
(esphome.screen_camera with tiles, size and bg) and the app serves one
BMP, a strip of squares with the corners rounded over each tile's own
colour; every tile draws its square out of it with LVGL's image offset
(LV_IMAGE_ALIGN_TOP_LEFT: the default centres a taller source). A third
online_image on the Guition holds the strip; it loads after the alert's
picture, a cover and the camera full screen, never under a card, in
standby or under a finger. The strip is served whole every time: ESPHome's
http_request logs a 304 as a failed request. Firmware 0.2.77.

Alert button: esp_screens_show_alert takes action and data; the app
performs the action once when the button's report (esphome.screen_alert,
ok) comes from any screen. show_alert keeps its seven fields, so every
firmware from 0.2.31 has it.

Media card and full-page media tile: a title or artist line that is too
wide rolls by (LV_LABEL_LONG_SCROLL_CIRCULAR) instead of ending in dots.

Full-page tiles are white or their own pastel like every other tile; the
tint in the state colour of firmware 0.2.62 to 0.2.76 is gone.

Host harness (27 checks) and bench Guition + local add-on on the Yellow:
docs/TEST_RESULTS_0291.md. CYD firmware 1,633,728 B, 89.0 %.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

tests/test_state_colours.py

@@ -59,7 +59,10 @@ class StateColours(unittest.TestCase):
 
     def test_the_tile_greys_and_lights_up_by_home_assistants_rule(self):
         self.assertIn('uint32_t accent=tile_controls::accent(t);', TILES)
-        self.assertIn('bool lit=w.full && on && t.lights_up() && available && !t.transparent;', TILES)
+        # A full-page card is white or its own pastel like every other card (firmware 0.2.77+; 0.2.62-0.2.76 tinted it).
+        self.assertNotIn('lights_up()', TILES)
+        self.assertNotIn('lights_up', MODEL)
+        self.assertIn('set_color(w.tile,LV_STYLE_BG_COLOR,lv_color_hex(theme::surface(t.background)));', TILES)
         self.assertIn('const uint32_t fill=slider_on?accent:theme::STATE_OFF;', TILES)
         self.assertNotIn('domain_accent', TILES)
         self.assertIn('frontend src/common/entity/state_active.ts', MODEL)